Quote Originally Posted by Alter View Post
3. Remaining in a lucid dream forever. I have had dreams which have seemed to last for months while only a single night passed in the real world. While this could possibly be extended to years using my dream extending techniques I don't see how it would be possible to remain in the dream world indefinitely.
All but this are impossible. While this would be VERY hard and require some very advanced technology, it's actually possible, it's just far out of our reach right now. At least, it's out of reach in a safety sense. You can keep giving people nutrients, water, and strong sedatives, but everybody knows this probably isn't very healthy. Interesting question, though. Maybe you could start a "List of Things You Can't Do in a LD" thread.